Sun simulators are widely used in the photovoltaic (PV) industry for the electrical characterization of solar cells and modules. With the help of artificial light, the solar spectra AM1.5G, or others, are approximated. A complete sun simulator measurement system needs to incorporate specific components beside the light source to assure very accurate current-voltage measurements. While there exists many different light sources in the prior art, there is hardly any solution for delivering accurate sun simulator measurement results, especially for the thin film silicon PV application.
The light spectra, the light homogeneity and the temporal stability of a light source is critical, but the same accounts for electrical contacting, without destroying the front and/or back transparent conductive oxide (TCO) contact of the solar cell, the accurate temperature distribution and control of the device under test (DUT), the low current switching and measuring and many other factors that must be fulfilled.
Some of the main disadvantages of sun simulators know in the prior art lie in the limited accuracies of the measurement systems. Beside that, most of the measurement systems used, are developed in the laboratory and do not fulfil the requirements of a photovoltaic production line environment, i.e. the sun simulators are to complex, difficult to calibrate and/or difficult to maintain.